﻿using System;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.ComponentModel.Composition.Hosting;
using System.ComponentModel;

namespace SL4_MVVM_MEF
{
[Export(typeof(IDeploymentCatalogService))]
public class DeploymentCatalogService : IDeploymentCatalogService
{
    private static AggregateCatalog _aggregateCatalog;

    Dictionary<string, DeploymentCatalog> _catalogs;

    public DeploymentCatalogService()
    {
        _catalogs = new Dictionary<string, DeploymentCatalog>();
    }

    public static void Initialize()
    {
        _aggregateCatalog = new AggregateCatalog();
        _aggregateCatalog.Catalogs.Add(new DeploymentCatalog());
        CompositionHost.Initialize(_aggregateCatalog);
    }

    public void AddXap(string uri, Action<AsyncCompletedEventArgs> completedAction = null )
    {
        DeploymentCatalog catalog;
        if (!_catalogs.TryGetValue(uri, out catalog))
        {
            catalog = new DeploymentCatalog(uri);
            if (completedAction != null)
                catalog.DownloadCompleted += (s, e) => completedAction(e);
            else
                catalog.DownloadCompleted += catalog_DownloadCompleted;

            catalog.DownloadAsync();
            _catalogs[uri] = catalog;
            _aggregateCatalog.Catalogs.Add(catalog);
        }
        //_aggregateCatalog.Catalogs.Add(catalog);
    }

    void catalog_DownloadCompleted(object sender, AsyncCompletedEventArgs e)
    {
        if (e.Error != null)
            throw e.Error;
    }

    public void RemoveXap(string uri)
    {
        DeploymentCatalog catalog;
        if (_catalogs.TryGetValue(uri, out catalog))
        {
            _aggregateCatalog.Catalogs.Remove(catalog);
        }
    }
}

}
